1. Field of the Invention
The invention is directed to a device for rotatably coupling two coaxial connecting elements, at least one of which is configured as a circular ring, and each of which has at least one annular surface that faces the corresponding surface of the other connecting element, but is spaced apart therefrom by a gap, such that the connecting elements are rotatable in opposite directions about an imaginary axis (axis of rotation) at the center of the annular connecting element and approximately perpendicular to the ring plane, wherein disposed in the gap between the two connecting elements is a rotary joint, configured as a single- or multi-row rolling bearing, for absorbing axial and radial loads and tilting moments.
2. Description of the Prior Art
Such rotary joints are used in an extremely wide variety of fields and an extremely wide range of sizes. Although the term “ball bearing” still tends to evoke concentric rings a few centimeters in diameter, rolling-bearing rotary joints of this kind now range up to eight meters in diameter. The circumference is then as much as 25 meters, comparable to the length of a passenger car on a train. All the same, for reasons of weight, the cross section of a ring should usually be no more than 100 to 200 square centimeters. Such delicate rings are not inherently rigid enough to counteract elliptical deformation, for example, especially since tremendous forces and/or torques can occur during operation. Each of the two rings is usually provided with coronally arranged fastening bores that serve to frictionally secure it to a support structure. This support structure must then be able to absorb any deformation forces that occur and to withstand them without noticeable deflection. If, for whatever reason, the structure is not able to provide the desired mechanical rigidity, then it is nearly impossible to introduce forces into the rings or have them absorb forces in order to counteract undesired deformation, and the design engineer is confronted with a nearly insoluble structural problem.
From these disadvantages of the described prior art arises the problem initiating the invention, that of improving a rotary joint of this kind in such a way that it becomes possible to introduce forces into the rings or have them absorb forces so as to counteract undesired, for example elliptical, deformation of the rings.